Hoping someone knowledgeable about paver patios can help with this one.
I am building a 20 x 30 raised paver patio. The area I am putting in has a significant slope towards a pond. Rather than excavating the entire area to bring it level, I have decided to install a retaining wall, and back fill inside to bring level. As a result, the area closest to the pond (which obviously is the lowest area) will have a fairly high retaining wall (6ft).
My first question has to do with back fill. I know I need 6-8" of road pack (screenings or 1/2" to fines), then 1" sand. In the areas that need significant back fill (4-5ft) I have heard of people using 3/4" stone. I had heard this stuff is 95% compacted as soon as it's dumped. The result is tamping every 8" - 1 ft, instead of every 2-4" with road pack. Does anyone have any experience with this? Suggestions or discouragement?
My main concern is this seems odd to me. The 3/4" will obviously have a more empty space than the road pack. Over time, won't the finer elements of the road pack settle into the 3/4" underneath?
My second question has to do with grading the patio for drainage. I know it needs to slope 1/4" every 2-3 ft. However I want he pavers to lay flush with the retaining wall, which I thought needs to be level. How do I do this? Which one gives? Do I slope the wall at the same grade?
versa-lok has a great set of youtube videos that cover the full build of the retaining wall; including back fill.
As for your second question, I don't understand how the slope will keep the pavers from being flush with the retaining wall... Your patio will slop towards the retaining wall; with the last row of pavers ending up flush with the top of the wall...